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To manage increasingly complicated 3D city models,a framework based on NoSQL database is proposed in this paper.The framework supports import and export of 3D city model according to international standards such as CityGML,KML/COLLADA and X3D.We also suggest and implement 3D model analysis and visualization in the framework.For city model analysis,3D geometry data and semantic information (such as name,height,area,price and so on) are stored and processed separately.We use a Map-Reduce method to deal with the 3D geometry data since it is more complex,while the semantic analysis is mainly based on database query operation.For visualization,a multiple 3D city representation structure CityTree is implemented within the framework to support dynamic LODs based on user viewpoint.Also,the proposed framework is easily extensible and supports geoindexes to speed up the querying.Our experimental results show that the proposed 3D city management system can efficiently fulfil the analysis and visualization requirements.